• Title/Summary/Keyword: THRESHOLD

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Fault Detection and Isolation using navigation performance-based Threshold for Redundant Inertial Sensors

  • Yang, Cheol-Kwan;Shim, Duk-Sun
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.2576-2581
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    • 2003
  • We consider fault detection and isolation (FDI) problem for inertial navigation systems (INS) which use redundant inertial sensors and propose an FDI method using average of multiple parity vectors which reduce false alarm and wrong isolation, and improve correct isolation. We suggest optimal isolation threshold based on navigation performance, and suggest optimal sample number to obtain short detection time and to enhance detectability of faults little larger than threshold.

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A Study for Effective Speaker Adaptation and a priori Threshold Updating in Speaker Verification (화자 인증에서의 효과적인 화자 적응과 a priori Threshold Updating에 관한 연구)

  • 조영훈;이수호;홍대희;고한석
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.491-494
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    • 2001
  • 실제 화자 인증기를 설계함에 있어서 발생하는 가장큰 문제는, 적은 Enrollment data로 화자 모델이 만들어 지므로 화자 인증기의 성능이 시간이 지남에 따라 굉장히 줄어들게 되는 것과, 미리 훈련된 데이터 만으로 Threshold를 설정함에 따라 차후 실제 사용 시에 발생하는 변이를 고려하지 못하여 역시 성능 저하의 문제를 발생시킨다는 것이다. 위의 문제를 해결하기 위해 이 논문은 화자 모델을 구성하는데 있어 MAP 방법을 적용하고, threshold를 Resetting하는 방법을 적용했다. 본 논문에서 제안한 방법으로 HTER값이 23%정도 줄어듦을 보여준다.

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Statistical Decision making of Association Threshold in Association Rule Data Mining

  • Park, Hee-Chang;Song, Geum-Min
    • Journal of the Korean Data and Information Science Society
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    • v.13 no.2
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    • pp.115-128
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    • 2002
  • One of the well-studied problems in data mining is the search for association rules. In this paper we consider the statistical decision making of association threshold in association rule. A chi-squared statistic is used to find minimum association threshold. We calculate the range of the value that two item sets are occurred simultaneously, and find the minimum confidence threshold values.

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Optimal Threshold for ECN Marking (ECN 마킹을 위한 적당한 Threshold)

  • 임재걸;이계영;장익현;윤준영
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.10c
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    • pp.172-174
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    • 2004
  • 무선 네트워크의 TCP 성능을 제고하기 위한 방법으로 ECN 방법이 심도 있게 연구되었다. 그러나, ECN 마킹을 위한 최적의 threshold에 대한 연구 결과는 찾아 보기 힘들다. 본 논문은 ECN 마킹을 위한 최적의 threshold를 찾는 식을 제시하고, ECN 전략을 적용하는 TCP의 페트리 넷 모형을 구축한 다음, 시뮬레이션을 통하여 제시된 식의 타당성을 검증한다. 또한 제시된 식의 실용화 방안도 제안한다.

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Selection of Threshold for Complex Objects Representation from the H,K Curvatures (H,K곡률에서 세밀한 물체의 표현을 위한 임계치의 선정)

  • 조동욱
    • Proceedings of the Korea Contents Association Conference
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    • 2003.05a
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    • pp.426-429
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    • 2003
  • This paper proposes the threshold value selection for surface classification of 3-dimensional objects. Pre-existing method which uses the H-curvature and K-curvature has limitation in the practical threshold value selection. For this, this paper proposes the threshold value selection by the statistical method. Finally, the effectiveness of this paper demonstrated by experiment.

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A Study on the Threshold of Avoidance Sector in the New Evaluation of Collision Risk

  • Jeong Tae-Gweon
    • Journal of Navigation and Port Research
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    • v.28 no.9
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    • pp.799-802
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    • 2004
  • Evaluation of the quantitative risk of collision plays a key role in developing the expert system of navigation and collision avoidance. This study analysed thoroughly how to determine the threshold of avoidance sector as described in the new evaluation of collision risk, and suggested the collision risk obtained by the alteration of course and/or speed in order to pass clear qf each danger zone as the threshold of avoidance sector.

Wavelet Transform Based Compression of Power Quality Signal (웨이브렛 변환을 이용한 전력품질 신호 압축)

  • Chung, Young-Sik;Kim, Cheol
    • Proceedings of the KIEE Conference
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    • 2006.11a
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    • pp.305-307
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    • 2006
  • The choice of threshold is an important in the compression algorithms. It plays a major role in the removal of coefficients which are not preserved the important features. In this paper two threshold method, hard threshold(HTH) and soft threshold(STH) are applied to the suggested wavelet based compression algorithm of power quality signal and compared the compression ratio and NMSE. The simulation results show that STH is bottom than HTH.

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Zerotree coding with local adaptive threshold (국부 적응 문턱값을 가지는 제로트리 부호화)

  • 엄일규;김유신;김재호
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.34S no.10
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    • pp.112-119
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    • 1997
  • Zerotreeimage coding is known as a simple and effective image comprssion algorithm. It has the property that the compression is generated in order of improtance. Conventionally, a fixed threshold is applied to the entire wavelet coefficients regardless of frequency and local features of an image. In this paper, we propose a new zerotree coding scheme with adaptive threshold. The adaptive threshold is determined by human visual characteristics. It is shown that the image quality of the proposed method is better than that of the conventional method.

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PERFORMANCE ANALYSIS OF A MULTIPLEXER WITH THE THRESHOLD BASED OVERLOAD CONTROL IN ATM NETWORKS

  • Park, Chul-Geun
    • Journal of applied mathematics & informatics
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    • v.5 no.3
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    • pp.643-658
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    • 1998
  • In this paper we analyze the performance of a statistical ATM multiplexer with bursty input traffic and two thresholds in the buffer by using queueing model. Two priority levels are considered for source traffic which is modeled by Markov Modulated Poisson Process to represent the bursty characteristics. Service time distributions of two priority sources are assumed to be same and deterministic for ATM environment. The partial buffer sharing scheme with one threshold may experience a sensitive state change around the threshold. But the proposed multiplexer with two thresholds avoids this hysterical phenominon to improve the system operation.

Statistical Decision making of Association Threshold in Association Rule Data Mining

  • Park, Hee-Chang;Song, Geum-Min
    • 한국데이터정보과학회:학술대회논문집
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    • 2002.06a
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    • pp.169-182
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    • 2002
  • One of the well-studied problems in data mining is the search for association rules. In this paper we consider the statistical decision making of association threshold in association rule. A chi-squared statistic is used to find minimum association threshold. We can calculate the range of the value that two item sets are occurred simultaneously, and can find the minimum confidence threshold values.

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